Measure the fork leg from the upper end / top of the cap to centre of the front axle. In the "long" setting it is 895mm, in the "short" setting it is about 860mm.
You should be careful with just pushing the forks through the triple clamps. Opposed to moving the spacers "dropping" the front will reduce the clearance of the front wheel with fully compressed suspension. Depending on the tire used and depending on how far you push the tubes through you might lock your front wheel after the next jump

"Dropping" the long forks by up to 30mm is safe and actually the recommended (by me) lowering for very light riders. Short & heavy guys should rather use the official lowering method (moving a spacer from on top of fork spring to below the damper piston which reduces the suspension travel and increases the spring preload.
Re: The rear shock: The lower spring support has a slot. Have a close look there. If the spring support in its cross section looks like an inverted "U" it is in the high setting and the shock MUST be connected to the cushion lever in the corresponding high hole.
To lower the bike you have to remove the shock from the bike, turn out the spring preload and turn the lower spring support around. This reduces the maximum travel of the shock.
If you only change the connection of the rear shock to the cushion lever without modifying the shock itself the rear wheel can travel too far resulting in the brake caliper hitting the exhaust

or the rear wheel disassembling the bike's tail

Crossed Up's bike is lowered as specified by Suzuki.
For importing the tank expect to pay VAT and a handling fee. The handling fee depends a lot on the mood of some -censored- at customs as they move more and more to the practice to employ a clearing agent for stuff that could be cleared by the recepient in the past. If you can clear yourself it's R25 as far as I remember. Clearing agent is a few hundred Rand

A very worthwhile alternative to the IMS is the Clarke tank. 16l is sufficient for me, the tank is very well made, looks great and leaves access to plugs etc. It fits like a glove once you have sourced two longer bolts and two small pieces of 10x1.5 stainless steel hydraulic tube as spacers for the tank bolt rubbers.
Topbox can get you one for a good price.